The coconut crab is the largest land-living arthropod in the world. It is a highly apomorphic hermit crab and is known for its ability to crack coconuts with its strong pincers in order to eat the contents. It is the only species of the genus Birgus (Birgus latro).

Robber crab

Coconut crab

Coconut crabs in Bora-Bora

Coconut crabs distribution map :
Coconut crab distribution map

Source and images : Wikipedia